The aim of the study was to investigate the accumulation of cadmium in the scales of Prussian carp (Carassius gibelio B.) as an indicator tissue of water contamination by cadmium. The study was carried out on 70 mature Prussian carp, which were placed in three 300L tanks. The fish were exposed to cadmium dissolved in water at a concentration of 0.0, 0.4 or 4.0 mg L-1 for a period of 84 days. After 42 and 84 days of exposure, 10 fish were randomly sampled from each tank. The fish were decapitated and all their scales were collected. The scales were rinsed and each was then carefully sectioned into an inner part and an outer part, removing the outermost growth ring, which most likely included scale increment from the exposure period. Cadmium concentration in the samples was then measured using the atomic absorption method. The analysis of the results showed that the concentration of cadmium in the scales increased with the duration of exposure and was significantly higher in the outer growth rings. The accumulation of cadmium in this part of the scales was correlated with the dose of cadmium and the duration of exposure. The results obtained confirmed the hypothesis that the concentration of cadmium in the outermost growth rings of fish scales reflects the most recent status of environmental contamination by this metal. Scales, which - unlike other tissues such as the liver and muscle - can be sampled non-lethally, seem to be an excellent bioindicator of environmental contamination by heavy metals.

27.4.2022